Platen adjusting means for typewriters



1964 R. R. GALLANT ETAL PLATEN ADJUSTING MEANS FOR TYPEWRITERS FiledJune 25, 1962 Fri...

IN V EN TOR. Rvq/na/a fi. Ger/lam Hal/at? N. Pms fan United StatesPatent PLATEN ADEUSTING MEANS FER TYPEWPJEERS Reginald R. Gallant,Bristc-i, (Iona, and Wallace M.

Preston, West Springfield, Mash, assignors to Underwood Corporati-an,New York, NFL, a. corporation of Delaware Filed June 25, 1962, Ser. No.2154,7525 Claims. (Cl. 17-149) This invention relates to typewriters andmore particularly to devices therein which facilitate the adjustment ofthe position of the platen roll therein in respect to typinginstrumentalities in order to establish suitable printing conditions forthe particular work that is required to be done.

Some typewriters embody a stop ring whereagainst the type bars strike inorder to control the depth of penetration of the typing blows into thepaper. However, the thickness of the work sheets and the number ofcopies required to be typed varies greatly and for this reason theplaten must be capable of adjustment in respect to the typinginstrumentalities in order to establish the proper conditions ofcontrolled typing blows.

Moreover, to facilitate best-quality typing, the machine must beconstructed to enable the ready installment of platens of varioushardnesses and properties suited to the particular work that is requiredto be done.

These features are generally known in the art but heretofore haveentailed structures of complex and expensive nature, taking up anexcessive amount of space and encumbering the carriage with undesirableweight.

It is an important object of the invention to provide simple,economically manufacturable and highly efficient means to facilitate theconvenient adjustment of a typewriter platen with respect to the typinginstrumentalities, and also in connection therewith to provide forcapability of convenient substitution of platens of desiredcharacteristics.

It is a further object of the invention to accomplish the foregoingobject by mechanism which is not only simple in nature but takes up aminimum amount of space while adding very little weight to the carriage.

Other objects of the invention will become readily evident from thedescription which follows and in the light of the form of the inventionwhich is illustrated in the drawings.

Now referring to the drawings, FIGURE 1 is an end elevation of atypewriter carriage looking rightwardly thereagainst but certain partsbeing shown sectioned,

FIGURE 2 is a front perspective illustration viewing the carriage asseen from the left, and

FIGURE 3 is an exploded-aspect perspective illustration of a platenmounting saddle element along with parts that normally are unitarytherewith.

Referring now more particularly to FIGURE 2, a platen roll hasoppositely reaching shafts or shaft ends indicated at 11 and 12 whichcarry usual platen turning knobs, one of these knobs being indicated at11a. In a usual manner, said shafts 11 and 12 carry respectively abushing 13 and a bushing 14, such bushings being peripherally grooved asat 15 and 16, respectively. The locations of said bushings 13 and 14along their respective shafts are defined in a usual manner by means notshown. The said platen roll 10 is mounted on a carriage structure whichincludes two carriage ends 17 and 13, carried upright in spaced relationon a carriage rail 29. In cooperation with usual trackways, not shown,said rail 20 guides the carriage for typing and return travels.

In FIGURE 1, a type bar is indicated at 21, striking a conventional stopring at 22, thereby to control the penetration of the type striking thework sheet on the platen.

The platen 19, by means of the peripherally grooved shaft-bushings 13and 14 thereon, is seated upon saddles 25, 26 of two part-circularsaddle elements 27, 28, the latter provided respectively in the carriageends 17 and 18. Said saddle elements 27, 28 have each a peripheral face36 in an eccentric relationship to the centers of the saddles 25, 26 andby such faces they are accommodated turnably in the respective carriageends within incompiete, circular bearing faces 31, see FIGURE 1. It willbe seen that said saddles 25, 26, are radially open in an upwarddirection and that the carriage ends are openmouthed or radially open inthe same direction generally as said saddles, thereby to allow theplaten, by its bushings 13, 14 to be placed or removed from said saddleelements.

Each of the saddle elements has integral therewith a rim 32 (FIGURE 3)flanking the outer side of the carriage end. On each saddle element,another rim is afforded by a plate 33 which is attached thereto byscrews 3 Because the peripheral faces 30 or" the saddle elements 27, 28extend around in the incomplete bearing faces 31 in excess of it isevident that the saddle elements are permanently carried in the carriageends.

The said saddle elements are interconnected for concerted rotativeadjustment in the carriage ends and to this end a shaft 35 (FIGURES land 2) is provided on the carriage parallel to the platen roll andexterior thereof. This shaft has at each end an arm 36 integrally formedthereon and each has a pin reaching into a fork of a related plate 38.The same screws 34 which attach the plates 33 to the saddle elements 25,26, serve also to attach the plates 38 thereto.

The plate belonging to the saddle element 26 on the right carriage endincludes forwardly of the platen shaft bushings 13, 14 an upreachinghandle 40. By movement of this handle the saddle elements are conjointlyadjustable. ln FIGURE 1 the handle 49 is shown in a middle position. Bymoving the handle forwardly and rearwardly to the indicated otherpositions, the platen roll will be relocated respectively forwardly andrearwardly a small distance in substantially a horizontal plane.

Both the plates 38 are provided with several corre sponding detentnotches 42 wherewith individual spring fingers 41 cooperate to retainthe adjustment. A pin 39 in the right carriage end 18, in cooperationwith a notch in the plate 38 thereat, establishes limits of adjustment.

The stated shaft 35 is rockably supported on the carriage frame by meanscomprising at each carriage end a bracket 43. The latter are eachsecured to the respective carriage ends 17, 18 by screws 45, in anoverlying relation to forward portions of the spring fingers 41 and saidbrackets 43 have each a half circular ear 44 which in conjunction Withthe underlying spring finger 41 affords a shaft hearing.

A releasable device 47 is provided at each carriage end to hold theplaten roll 16 in position upon the saddles 25, 26. In the specificembodiment of the invention shown in the drawings, these devicescomprise each a roller 48, and these rollers normally overlie thebushings 13 and 15 in their respective grooves 15 and 16. The saiddevices embody each a lever 49 to support one of the rollers and theselevers have pivotal support at 56* on the opposite carriage ends. Saiddevices include each also a lever 51 having an operating finger piece 52and being pivoted at 53. Bowed links 54 of resilient character connectthe levers 49 and 51 at each carriage end.

Normally, as shown, the said devices hold the platen n; roll seated inthe saddles 25, 26. However, if the finger pieces 52 are forcedforwardly, their related levers 49 swing rearwardly and will place therollers in a position indicated at 48a, FIGURE 1 This frees the platenroll Iii for upward removal. It will be seen that the pivotal joint ofeach bowed link 54 with the forward arm of its related lever 51constitutes a toggle lock for the lever 49 supporting the roller. Thebowed links 54- are of slightly excessive length so that they willstrain as the rollers descend on the platen shaft bushings 14, 15. Thepressure with which the rollers 48 bear down is sufiicient to counteractthe upward pressure of the usual feed rolls, not shown, that bearupwardly against the platen roll. However, the downward pressure of therollers 4% permit sufliciently free turning of the saddle elements 27,28 in the carriage ends to permit their adjustment.

The novel platen adjusting structure of this invention is applicable toother typewriting machine requiring variable correlating of a platenwith typing means, inclusive also machines wherein the typing meanstravels instead of the platen.

What we claim is:

1. In a typewriter or similar office printing machine having a platenroll formed at its ends with a pair of end shafts, a pair of framemembers supporting said pair of shafts, said platen roll being removablefrom said frame members, and printing means movable toward said platenroll for effecting imprints, a device for adjusting the position of saidplaten roll with respect to said printing means according to thethickness of the work sheet and number of copies, comprising incombination:

(a) a pair of part-circular elements, each one rotatably mounted on acircular portion of a radially open slot provided on each one of saidpair of frame members,

(b) a saddle provided eccentrically on each one of said elements andadapted to rotatably support the corresponding shaft of said pair, saidsaddles being radially open in the said frame members in the samedirection as the said slots thereby to enable removal of said platenroll,

(c) the circular portions of said slots and the partcircular magnitudeof said elements being in excess of 180 degrees in order to preventremoval of said elements from said frame members when said platen rollis removed from the latter,

(d) and means including manipulative means for simultaneously rotatingsaid circular elements to adjustably displace said platen roll withrespect to said printing means.

2. In a typewriting machine having a work-sheet-supporting platen withopposite shaft extensions, and having a platen-roll-supporting frame aswell as printing means operable against said platen roll;

(a) means adapted in cooperation with said shaft extensions to mountsaid platen roll adjustably positionable into different imprintregulating positions in respect to said printing means and comprising,

(a1) two saddle elements having each an open saddle thereon to receiveand locate said platen roll by its shaft extensions and thus to definethe location of the platen axis, said saddle elements having circularmounting faces which surround said saddles over an angular rangeexceeding 180 degrees but in an eccentric relationship to the platenaxis by said saddles,

(a2) said mounting means comprising further means on said frame,cooperative with said mounting faces of said saddle elements over anangular range sufficiently exceeding 180 degrees so as to mount andretain said saddle elements, adjustably turnable on said frame,

(b) said saddle elements and said frame having openings for said shaftextensions in generally corresponding directions leading from saidsaddles, thereby to facilitate receipt and, removal of the platen roll,

(c) and means carried on said frame and opera-tively interconnectingsaid saddle elements exterior of the platen roll, to facilitateconcerted turning adjustments of the saddle elements on said frame andthereby to give said platen roll different imprint regulating positions.

3. in a typewriting machine having a work-sheet-supporting platen, aplaten-roll-supporting frame and printing means operable against saidplaten roll;

(a) an eccentric mounting means for each opposite end of the platenroll, carried adjustably turnable directly on said frame to adjust theplaten roll transversely of its length into different imprint regulatingpositions in respect to said printing means,

(b) and means to effect concerted turning adjustments of said twomounting means, comprising means supported on said frame and exterior ofsaid platen roll to interconnect said mounting means,

(c) said platen roll having at least at one end thereof a shaftextension and the eccentric mounting means for at least such one end ofthe platen roll constituting a saddle element for receipt of said shaftextension,

(d) said saddle element having a circular mounting face over an angularrange exceeding degrees and further having an open saddle defining theplaten axis in an eccentric relationship to said circular mounting face,

(e) said frame comprising means cooperative with the mounting face ofsaid element in an angular range exceeding 180 degrees, to mount andretain said saddle element turnably thereon,

( said saddle element and the frame thereat having openings insubstantially corresponding directions away from said open saddle,thereby to facilitate receipt and removal of said shaft extension.

4. The invention set forth in claim 3, said structure furthercomprising,

(g) means movable to and from cooperative relation with said shaftextension of the platen roll, respec tively to confine such shaftextension turnably seated on said saddle, or to facilitate platen-rollremoval,

(h) said movable means including means governed by said saddle elementin accord with its varying axis defining positions of its saddle torender said shaft extension turnably seated in said saddle as well as toallow turning adjustments of said saddle element.

7 5. In a typewriting machine having a work-sheet-supporting platenroll, a platen-roll-supporting frame and printing means operable againstsaid platen roll;

(a) an eccentric mounting means for each opposite end of the platenroll, carried adjustably turnable directly on said frame to adjust'theplaten roll trans-- versely of its length into different imprintregulating positions in respect to said printing means,

(b) means to effect concerted turnin adjustments of said two mountingmeans, comprising means supported on said frame and exterior of saidplaten roll to interconnect said mounting means,

(0) said platen roll having at least at one end thereof a shaftextension and the eccentric mounting means for at least such one end ofthe platen roll constituting a saddle element for receipt of said shaftextension,

(d) said saddle element having a circular mounting face over an angularrange exceeding 180 degrees and further having an open saddle definingthe platen axis in an eccentric relationship to said circular mountingface,

(e) said frame comprising means cooperative with the mounting face ofsaid element in an angular range exceeding 180 degrees, to mount andretain said saddle element turnably thereon,

(f) said saddle element and the frame thereat having openings insubstantially corresponding directions away from said Open saddle,thereby to facilitate receipt and removal of said shaft extension,

(g) and means movable to and from a cooperative relation with said shaftextension, respectively to confine such shaft extension turnably seatedon said saddle, or to facilitate platen-roll removal,

(h) said movable means comprising a resilient provision for pressing theroller against said shaft extension regardless of the prevailingtransversely adjusted position of the platen roll, said platen beingcapable of rotation and the saddle element being capable of turningadjustment.

References Cited in the file of this patent UNITED STATES PATENTSMcLaughlin Mar. 14, 1916 Hokanson Apr. 26, 1927 Harrold et al. June 20,1939 Helmond Sept. 5, 1939 Ritz Sept. 4, 1951 Dooson Jan. 29, 1952FOREIGN PATENTS Germany Apr. 3, 1922

1. IN A TYPEWRITER OR SIMILAR OFFICE PRINTING MACHINE HAVING A PLATENROLL FORMED AT ITS ENDS WITH A PAIR OF END SHAFTS, A PAIR OF FRAMEMEMBERS SUPPORTING SAID PAIR OF SHAFTS, SAID PLATEN ROLL BEING REMOVABLEFROM SAID FRAME MEMBERS, AND PRINTING MEANS MOVABLE TOWARD SAID PLATENROLL FOR EFFECTING IMPRINTS, A DEVICE FOR ADJUSTING THE POSITION OF SAIDPLATEN ROLL WITH RESPECT TO SAID PRINTING MEANS ACCORDING TO THETHICKNESS OF THE WORK SHEET AND NUMBER OF COPIES, COMPRISING INCOMBINATION: (A) A PAIR OF PART-CIRCULAR ELEMENTS, EACH ONE ROTATABLYMOUNTED ON A CIRCULAR PORTION OF A RADIALLY OPEN SLOT PROVIDED ON EACHONE OF SAID PAIR OF FRAME MEMBERS, (B) A SADDLE PROVIDED ECCENTRICALLYON EACH ONE OF SAID ELEMENTS AND ADAPTED TO ROTATABLY SUPPORT THECORRESPONDING SHAFT OF SAID PAIR, SAID SADDLES BEING RADIALLY OPEN INTHE SAID FRAME MEMBERS IN THE SAME DIRECTION AS THE SAID SLOTS THEREBYTO ENABLE REMOVAL OF SAID PLATEN ROLL, (C) THE CIRCULAR PORTIONS OF SAIDSLOTS AND THE PARTCIRCULAR MAGNITUDE OF SAID ELEMENTS BEING IN EXCESS OF180 DEGREES IN ORDER TO PREVENT REMOVAL OF SAID ELEMENTS FROM SAID FRAMEMEMBERS WHEN SAID PLATEN ROLL IS REMOVED FROM THE LATTER, (D) AND MEANSINCLUDING MANIPULATIVE MEANS FOR SIMULTANEOUSLY ROTATING SAID CIRCULARELEMENTS TO ADJUSTABLY DISPLACE SAID PLATEN ROLL WITH RESPECT TO SAIDPRINTING MEANS.